CVE-2026-23346

A flaw was found in the Linux kernel, specifically within the arm64 architecture's I/O memory mapping (ioremap_prot) functionality. On systems with Privileged Access Never (PAN) enabled, a local user could exploit this by triggering a scenario where the kernel attempts to access a user memory mapping with incorrect permission controls. This leads to the kernel being unable to read from memory, resulting in a system crash and a denial of service.

This flaw is specific to ARM64 systems with PAN (Privileged Access Never) enabled. When generic_access_phys() passes user-derived pgprot_t to ioremap_prot(), the permission bits from user mappings are incorrectly preserved, causing kernel access faults when accessing /proc/pid/environ or similar interfaces. The crash is a DoS rather than a security bypass.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.